[NA-User] 4 serial port card

David A. Pruett k8cc at comcast.net
Sun Dec 12 22:11:21 EST 2004

Bill, Bob, et al:

I ran into the PCI/COM wall last fall when we were prepping for our VE1JF 
trip for the 2003 CQWW SSB.  We were taking our own computers (to run NA) 
rather than running WrongLog which was on the host station's PCs.  The 
computers were these cute little Acer P-200 desktops which I got at a 
computer show for $75 each with a 2 GB HDD, single COM, single LPT, a 
CD-ROM and 32 MB of RAM.  The problem with small form factor PCs is limited 
expandability - there were only two slots - one a PCI and the other a combo 

Since this was a phone contest, the ISA slot was taken by a W9XT Contest 
Card.  We needed two COMs on one computer (radio & network) and three on 
the other (radio, network, and packet).  I found PCI single-COM cards at 
CompUSA which worked fine for the first computer after some experimentation 
to determine what the configuration program used as the default IRQ.

For the other computer, I looked very hard for even a dual port PCI serial 
card which would work with NA.  While I could find dual port PCI COM cards, 
they all suffered from a common shortcoming: the two ports both shared a 
common interrupt request line (IRQ) and the COM port handlers in NA are 
designed to require separate IRQs for each port.  CT has the same 
limitation.  TRLog doesn't because it polls the COM ports and doesn't use 
IRQs; however for this reason it's limited to 4800 baud.

Ultimately, for the 'JF trip what I did was rummage through my junk box of 
old cards and found an ISA card with two ports with settable IRQs.

Unfortunately, I don't have a good answer for Bill right now.  If your 
motherboard has two COMs on board, you can probably add a third COM with 
the commonly available single-COM PCI cards.


At 02:32 PM 12/12/04 -0600, Robert Pack (NX5M) wrote:
>If you have two you could just add another dual port card.
>That is what I did with all my stuff.
>Bob NX5M
>----- Original Message -----
>From: "Bill Feissner" <ai3q at arrl.net>
>To: <na-user at contesting.com>
>Sent: Sunday, December 12, 2004 1:51 PM
>Subject: [NA-User] 4 serial port card
> > Hello all,
> > Anyone have any ideas on where to get an inexpensive PCI 4 serial port
> > card?  If you already have 2 do you need to buy a 4 port card or just a
> > 2 port card to add to the 2 on the motherboard? I'm far from a computer
> > wiz as you can see. Any thoughts and help appreciated.
> > 73,s de AI3Q, Bill Feissner
> >
> >
> > _______________________________________________
> > NA-User mailing list
> > NA-User at contesting.com
> > http://lists.contesting.com/mailman/listinfo/na-user
> > NA on the web:  http://www.datomonline.com/
> >
> >
> >
>NA-User mailing list
>NA-User at contesting.com
>NA on the web:  http://www.datomonline.com/

More information about the NA-User mailing list